Typically fuel is delivered from a fuel tank of a vehicle to the fuel system of an engine by means of a fuel pump. The fuel delivery circuit also typically includes a fuel filter downstream of the fuel pump and a fuel pressure regulator to regulate the fuel pressure downstream of the pump. Smaller vehicles, such as motorcycles, scooters and snow mobiles, and small watercraft, such as jet skis, have often relied on more simple fuel delivery systems, often using gravity to deliver fuel from a fuel tank to the fuel system, e.g. one or more carburettors, of the engine. Fuel injection systems are commonly replacing carburettors in such small vehicle applications, requiring higher fuel pressure than can be provided by a simple gravity feed. Furthermore, packaging constraints and alternative placements of the fuel tank may not provide sufficient gravity head between the fuel tank and the fuel system of the engine to permit the use of such gravity feed method of fuel delivery.
Typically in larger vehicles, such as cars or trucks, the fuel pump is provided within the fuel tank and the size, weight and packaging of the fuel delivery system is not particularly constrained due to the overall volume of the fuel tank and the size of the vehicle. However, in smaller vehicle applications, the small volume of the fuel tank and difficulties in providing access to the interior of the tank can makes the location of the fuel pump within the tank disadvantageous as it causes a significant reduction in the overall fuel capacity of the fuel tank and difficult assembly and maintenance procedures. Furthermore, strict packaging and weight constraints place limitations on the design, size and weight of inline fuel delivery components for use in such applications, rendering systems typically used for larger vehicles, such as cars, unsuitable. Also, due to the lower cost of such small vehicles, the cost of manufacturing and assembly of the fuel delivery system becomes more critical.
To improve fuel delivering, it has been proposed, for example in U.S. Pat. No. 3,658,444, a fuel delivery module comprising a fuel tight housing having a fuel inlet and at least one fuel outlet, a fuel pump located within a first chamber defined within the housing, said fuel pump comprising an electric motor and a positive displacement pump assembly drivingly connected to the motor for pumping fuel from the fuel inlet to said fuel outlet, at least a substantial part of said housing being formed from a plastic material, wherein one or more electrical conductors for supplying electrical energy to the electric motor exit through a wall region of the housing surrounding or adjacent a lower pressure region of the first chamber to be connectable to an electrical connector.
There are still some drawbacks with the existing fuel delivery module such as an assembly process too complicated and some sealing problems.